Muscle System

Question 1

What ability do all muscles have?

Answer 1

The ability to contract

Question 2

What type of tissues are muscle cells?

Answer 2

Excitable tissues

Question 3

What are the three types of muscles?

Answer 3

• Skeletal
• Cardiac
• Smooth

Question 4

What type of muscle is striated and under voluntary control?

Answer 4

Skeletal muscle

Question 5

What type of muscle is striated and involuntary?

Answer 5

Cardiac muscle

Question 6

What type of muscle is innervated by the autonomic nervous system?

Answer 6

Smooth muscle

Question 7

What is the primary role of skeletal muscle?

Answer 7

Allow locomotion and movement of limbs

Question 8

What physiological processes are regulated by smooth muscle?

Answer 8

• Circulation
• Digestion
• Respiration
• Reproduction
• Waste removal

Question 9

What makes up the meat of livestock animals?

Answer 9

Skeletal muscle

Question 10

How do nearly all skeletal muscles attach to bone?

Answer 10

Using tendons

Question 11

What is the role of flexor muscles?

Answer 11

Decrease angle between the segments

Question 12

What is the role of extensor muscles?

Answer 12

Increase the angle between segments

Question 13

What do adductor muscles do?

Answer 13

Pull a limb toward the median plane

Question 14

What do abductor muscles do?

Answer 14

Move the limb away from the median plane

Question 15

What are cutaneous muscles responsible for?

Answer 15

Allow movement of skin

Question 16

What is the connective tissue covering the entire muscle called?

Answer 16

Epimysium

Question 17

What does perimysium cover?

Answer 17

Bundles of muscle

Question 18

What is the connective tissue covering of each muscle fiber?

Answer 18

Endomysium

Question 19

What is the sarcolemma?

Answer 19

Membrane surrounding the muscle fiber

Question 20

What is the specialized form of endoplasmic reticulum in muscle fibers?

Answer 20

Sarcoplasmic reticulum (SR)

Question 21

What are repeating units within muscle fibers called?

Answer 21

Sarcomeres

Question 22

What are the two types of filaments in a sarcomere?

Answer 22

• Thick filaments
• Thin filaments

Question 23

What do I bands contain?

Answer 23

Only thin filaments

Question 24

What do A bands contain?

Answer 24

Both thick and thin filaments

Question 25

What happens to the H zone during muscle contractions?

Answer 25

It disappears

Question 26

What are thin filaments primarily made up of?

Answer 26

Actin

Question 27

What protein wraps around actin strands?

Answer 27

Tropomyosin

Question 28

What are the components of troponin?

Answer 28

* Troponin T * Troponin C * Troponin I

Question 29

What are thick filaments composed of?

Answer 29

Myosin

Question 30

What is the role of myosin heads?

Answer 30

Bind actin and catalyze the conversion of ATP to ADP + Pi

Question 31

What happens when myosin heads are activated by ATP?

Answer 31

They attach to actin and pull during the power stroke

Question 32

What is the myoneural junction?

Answer 32

The site where a motor neuron stimulates a muscle cell

Question 33

What is an action potential?

Answer 33

Impulse resulting from depolarizing and repolarizing the nerve cell membrane

Question 34

What neurotransmitter is released at the motor end plate?

Answer 34

Acetylcholine

Question 35

What happens to acetylcholine after it binds to muscle membranes?

Answer 35

It is rapidly broken down by acetylcholinesterase

Question 36

What is the effect of curare?

Answer 36

Acts as an acetylcholine antagonist

Question 37

What does botulinum toxin do?

Answer 37

Acts as an acetylcholine antagonist causing paralysis

Question 38

What is the function of the calcium channels during muscle contraction?

Answer 38

Allow calcium to flow into the cell

Question 39

What is the role of calcium in muscle contraction?

Answer 39

It binds to the troponin complex

Question 40

What does the power stroke do?

Answer 40

Pulls the actin towards the center of the sarcomere

Question 41

What happens to the myosin head during relaxation?

Answer 41

It binds ATP and loses affinity for actin

Question 42

What is rigor mortis?

Answer 42

Condition where myosin head binds irreversibly with actin due to ATP depletion

Question 43

What is muscle tone?

Answer 43

A slight state of tension in muscles even at rest

Question 44

What is an isometric contraction?

Answer 44

Muscle contracts against a load but does not shorten

Question 45

What is an isotonic contraction?

Answer 45

Muscle shortens as it contracts

Question 46

What happens to a muscle that is not used?

Answer 46

It will atrophy or shrink in size